In the Book of Genesis, Moses tells the story of Cain and Abel who were brothers born to Adam and Eve after sin entered the world. One day Cain and Abel brought an offering of sacrifice before the Lord. Cain offered fruit from the field while Abel sacrificed one of the sheep from his flock. God approved of Abel’s offering and rejected Cain’s offering.
Many have speculated about why God accepted the sacrifice of Abel’s sheep and rejected Cain’s offering of fruit. Paul gives the most obvious answer to us in the book of Romans: “For the wages of sin is death…” (Romans 6:23, NASB). Human achievement is not enough to atone for sin. Death is the only acceptable punishment.
Notice the difference between the two offerings brought to the Lord. Cain brought the best fruit he had to offer from his labors as a field worker. Able was a shepherd and brought the best of his flock. The difference was that Able sacrificed the life of an animal in keeping with God’s instructions. Moses does not tell us specifically that God instructed them how to bring sacrifices, but it is clear that God informed Cain of His disobedience:
“Then the Lord said to Cain, ‘Why are you angry? And why has your countenance fallen? If you do well, will not your countenance be lifted up? And if you do not do well, sin is crouching at the door; and its desire is for you, but you must master it’” (Genesis 4:6-7).
Apparently, Cain was enraged that God would demand a blood sacrifice. I can imagine him saying, “If God wants blood then I will give him blood! How about the blood of my brother Abel!” Instead of sacrificing a lamb from Abel’s flock, he sacrificed his brother in a deliberate act of rebellion. Cain would suffer the consequence of murdering Abel for the rest of his life.
The blood sacrifice would be the primary element of worship to God throughout the entire Old Testament scriptures. The author of the book of Hebrews describes the need for the shedding of blood for the atonement of sin: “And according to the Law, one may almost say, all things are cleansed with blood, and without shedding of blood there is no forgiveness” (Hebrews 9:22).
This is why John the Baptist introduced Jesus by shouting out “Behold, the Lamb of God who takes away the sin of the world!” Jesus would become God’s final sacrifice for sin.